In medical imaging, a region-of-interest (ROI) is typically used to denote a region, which can be one-dimensional, two-dimensional or three-dimensional, from which data is acquired. The data is then, in turn, used to generate one or more images. It is critical to select a ROI of the appropriate size and location in order to acquire images that are as clinically relevant as possible.
The ROI needs to be large enough and in the right location to cover the complete structure being investigated. However, the ROI should not be larger than needed in order to maximize resolution. For imaging modalities capable of displaying a live image, such as ultrasound, having a smaller ROI will help to ensure that the maximum achievable frame rate of the live image is realized. An ROI that is larger than necessary will result in a reduced frame rate. Additionally, having too large of an ROI may also result in lower spatial resolution, which may lead to images which are not as clinically useful.
Again, using conventional ultrasound as an example, it is typically desired to center the object being imaged in a field-of-view (FOV) of the probe. According to conventional techniques, the user acquires a two-dimensional image and then determines the ROI based on this two-dimensional image. However, since the two-dimensional image typically does not include any elevational information, it is impossible for the user to know if the ROI is appropriately placed. Additionally, it is difficult for the user to determine if the object is centered within the field-of-view of the probe since the user has only a two-dimensional image for reference.
For these and other reasons, there is a need for an improved method and system for medical imaging.